Motion Blur, Shutter Speed and Framerate... how are they tied together in UE?

Im really struggling trying to figure out how to control motion blur in unreal in the same way that its done with a dslr. Im hoping someone can shed some light on this workflow…

On a normal camera, the shutter speed is one of three controls you have in order to get more light into the camera. Its side effect is motion blur. Fast shutter speeds means little motion blur but darker exposoure, and slow shutter speeds means lots of motion blur but brighter exposure. In certain type of timelapse photography, the shutter speed is set extremely long so that you can get photos of rivers and waterfalls that look like mist. You can take a picture of the night sky and get really cool ‘star streak’ effect. This is all controlled by the shutter speed on the camera.

But it seems the motion blur controls in UE are either extremely limited, or are currently broken (UE 5.1.1). Im rendering cinematics, not making games. It seems that changing the shutter speed on the CineCameraActor only does half of whats its supposed to do… (if I have exposure set to manual, then yes changing the shutter speed increases or decreases the exposure) - but it doesnt have any effect on the motion blur.

I hop over to the post process volume, and there are 4 rollouts in the motion blur section, but only the first one seems to do what the tooltip says. The “Amount”… but it only goes from 0 to 1 where 0 means no motion blur, and 1 seems to be the max (which honestly isnt that much).

I cant seem to get more motion blur no matter what I do. The Max setting doesnt change anything, nor does the Target FPS, or the Per Object Size… Changing the shutter speed in either the PPV or on the camera has no effect.

Im at a loss as to what Im doing wrong here. is there no way to hold the shutter open for a really long time to get a ‘streak’ type of render from something moving? Is the 0 - 1 range of effect all that UE can achieve through the Movie Render Que?

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Bumping this… anyone have info on how to handle motion blur like on a physical camera?

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Bumping this, I want sharp videos